Acoustic grille cloth



Sept. 20, 1932. ABBOTT 1,878,570

ACOUSTIC GRILL! CLOTH Filed Feb. 17, 1932 3 p) A? w A? INVENTOR.

fiQF/asv 77/7550 r; BY

M ATTORNEY.

Patented Sept. 20, 1932 ALFRED T. ABBOTT, OF PHILADELPHIA, PENNSYLVANIA ACOUSTIC GRILLE CLOTH' Application filed February 17, 1982. Serial No. 593,555.

This invention, generally stated, relates to the Weave of fabrics and has more particular relation to the fabrication of a cloth particularly adapted for use in connection with 6 grilles of radios.

As at present practiced the grille cloth of a radio is fabricated in a fashion calling for an ordinary weave with ordinary yarn. Practice has demonstrated that the air waves 10 from the loud speaker impinge upon conven tional grille cloths in such manner as to mufile or deaden the tones desired to be employed. Practical demonstration has brought forward the fact that it is because of the plain 'or net woven fabric that these deadened or muffled tones result.

The leading object of the present invention may be said to reside in the providing of a loosely woven fabric for the grilles of radios designed to accentuate the acoustic properties of a radio emanating through a grille cloth as positioned before a loud speaker so as to mellow and smooth out, as it were, the sound Waves of the instrument.

A further object of the present invention is to provide a grille cloth of the character stated made up of a cotton warp and two different kinds of wefts or fillings wherein one filling is silk-like to add luster to the cloth and makes a loose weave with the warp ends, and wherein the other weft or filling is a specially constructed yarn having knotlike protuberances thereon, which yarn functions to pull the loose weave threads together so that when the yarn is floated upon the back of the fabric an embossed effect is obtained upon the front of the fabric, and when the yarn is floated upon the front of the fabric a similar embossed effect appears upon the reverse side of the fabric, whereby the warp ends are prevented from slipping so that the embossed effect is maintained in fixed position.

A further object of the present invention is to provide a grille cloth of the character stated in which interstices or openings occur between adjacent embossed portions of the fabric. whereby loud speaker tones may pass smoothly through theseopenings between embossed portions of the cloth in contradistinction to having the loud speaker tones impinge directly upon an ordinary plain or knit woven surface.

With the above and other objects in view, the invention consists of the novel construction hereinafter described and finally claimed.

The nature, characteristic features and scope of the invention will be more fully understood from the following description taken in connection with the accompanying drawing forming part hereof, and in which:

Fig. l is a face View, more or less diagrammatically illustrated, of a fabric embodying the invention;

Fig. 2 is a view in cross section of Fig. 1, drawn to an enlarged scale;

Fig. 3 is a fragmentary View more or less diagrammatically illustrated upon an enlarged scale of a portion of the fabric shown in Fig. 1;

Fig. 4 is a view of a so-called knot-yarn having spaced knot-like protuberances thereon; and

Fig.5 is a view in elevation of a radio illus'trating a grille cloth embodying the invention applied thereto. 7

For the purpose of illustrating my invention I have shown in the accompanying drawing one form thereof which is at present preferred by me, since the same has been found in practice to give satisfactory and reliable results, although it is to be understood that the various instrumentalities of which my invention consists can be variously arranged and organized and that my invention is not limited to the precise arrangement and organization of the instrumentalities as herein shown and described.

In the fabrication of my grille cloth according to the present invention I weave a very loose fabric made up of cotton warps and two different kinds of wefts or fillings.

The warp of the fabric comprises cotton 1 threads. The wefts or fillings comprise first a silk-like filling which makes a loose weave with the cotton warp ends, and second, a

filling comprising specially constructed knotyarn that acts like stitches and pulls the loose weave threads together to form an embossed design. This knot-yarn is floated upon the back of the fabric to produce an embossed effect upon the front of the fabric and is floated upon the front of the fabric to produce the same embossed effect upon the reverse side of the fabric. The rough or knotyarn prevents slipping of the cotton warp ends so that a permanent or non-shifting design is secured.

Referring to the drawing in detail, and with more especial relation to Figs. 1 to 4, the reference numeral designates thecotton warps of the fabric. The wefts form the filling. This filling comprises silk or arti ficial silk threads 11 in order to provide luster or sheen to the completed fabric. The wefts 11 are fabricated to make a loose weave. with the cotton warp ends. Paralleling the wefts 11 but spaced therefrom are other wefts 12..to.comp lete the filling. These wefts 12 .7 comprise strands of so-called knot-yarn whichisnot obtained in the open market in: generalbusiness transactions but has to be speciallyselected. As best seen in Fig. 4, thisv yarn is;roughened and is provided at regular intervals, ir practiceabout one inch apart, with knotrlike protuberances 13. The function ofthe knot-.yarn is that of'pulling the loose-weave together as it is alternately floatedupon the back and front of the fabric to provide an embossed effect bothupon the front and the back of the fabric. The knotlikeprotuberances of the floated yarn serve to. prevent slipping of the warpends, thereby providing the'embossed design effect. While the fabric is loosely woven, it is strengthened by-theknot yarn so that the warp, as-designed, may open up and allow the-tones of the loud speaker to pass freely and smoothly throughthe interstices or openings-14. see Figs. 1 and 3, which are arranged between adjacent embossed portions of the fabric. In this connection it isto be noted that the back oftheegrillecloth as fabricated provides-an unevenLsurface so that the tones-from the loud speaker do not impinge upon afiat grille cloth surface asin the case of an ordi-- nary-plain or 'net woven fabric, but on the contrary impinge upon a roughened or un-- even surface thereby sufficiently breaking up thertone wavesto mellow and soften them.

What is claimed is:

l. A loosely woven grille cloth for radios, said cloth having an embossed design secured against displacement by means of a specially constructed knot-yarn filling.

2. A loosely woven grille cloth for radios, said cloth having an embossed design arranged both upon the back and the front of said cloth and secured against displacement by means of a specially constructed knotyarn filling.

3. A loosely woven grille cloth for radios, said'cloth having an embossed design arranged both upon the back and the front of saidcloth and secured against displacement by means of a specially constructed knotyarn filling, there being interstices or. open: spaces between adjacent embossed portions of the cloth.,

4. A loosely woven grille cloth for; radios comprised ofcotton warps anda filling made up of silk-like threads and a;.knot;yarn of. which theformermakes a loosewcave with. the warp ends and of which the latter-fund tions to pull the threads of the loose. weave together when floated upon the. backbtthc' fabric to provide an embossedQdesignonthe front of the fabric and when floated irponthcf front of the fabric'provide a. similar embossed effect upon the reverse sideof-the fabric.

5. A loosely woven grille clothfor: radios comprised of cotton warps and a filling made up of silk-like'threads and almot-yarirof. which the former makes a lmse-weayewith the warp ends and of which :the latterfunc-- tions to pull the threads of theilooselweave; together when floated upon the-back-ofthie. fabric to provide an embossed design on :the frontof the fabric and when floatedupon the front of the fabric provide a similar cmbossed effect upon the reverse side-of'thefabric, said knot-yarn serving toprevent slipping off, said warp ends to maintain said embossed design in relatively permanent position.

6. Theherein described manner of making a grille cloth for radios which consists in taking cotton warps and two different kinds of weftsor filling, one being silk-like and the other a=rough yarn, and weaving the silk-like wefts with the cotton warp ends to provide aloose weave and causing said rough yarn to pull said loose weave together by floating said yarn upon the fabric back to providev an. embossed. effect on the fabric front, and causing said yarn to float upon the fabric front to provide a similar embossed effectupon the reverse side of the fabric, said rough yarn serving to prevent slipping of the warp ends.

ALFRED T. ABBOTT. 

